I don't mind people asking for notes but I do mind when they ask for it every class...even when they're there....

One of my lab partners for Chem always asked to see my notes and copy them. Our instructor has us copy down everything thing we do, see, and hear while conducting experiments. Yet, eventhough we're working on the same stuff, she always asking to see my notes to copy. Even my other lab partner got annoyed at it.

I never took notes. Occassionally people would ask to borrow mine and I'd just end up explaining what we learned to them instead. Of course, nobody really talked to me anyway, so that was pretty rare too.

I actually feel the same way. I don't mind sharing it but when I feel like
they are already being demanding, stretching my patience and asking too much,
that's the time that I do mind. I'm not their secretary. I don't work for them.

Also, listening and writing down notes at the same time is no easy feat.
It's (just like you said) hard work.

People who don't appreciate this don't have the right to demand your notes.

I always say yes but I always give them a warning that they may not be able to read or follow them.

My notes are written very specific to me, I write in my own language (use symbols instead of words, use movie/show quotes that reminds me of the topic, etc.) and I only write down certain things I feel are important, or things that I don't already know. So my notes tend to be a lot shorter, chopper, and harder to decipher then most other peoples notes. As a result people tend to only ask me once...